The Ebola outbreak in West Africa: a story of related public health challenges and a pointer to solutions to mitigate the inevitable next outbreakPeter Nsubuga
The Pan African Medical Journal. 2014;19:48. doi:10.11604/pamj.2014.19.48.5336

The current Ebola outbreak in West Africa has the world once again
gripped by the threat of a zoonotic disease that has spread into
several countries [1, 2]. While
the underlying factors that have led to an increasing frequency
of zoonotic disease outbreaks
are complex, including population pressure and rapid movement between
locations [3-5]
in most of these epidemicsthere are least three related key drivers
- a challenge of initial detection and appropriate investigation
and response to a cluster of suspected cases, a challenge of management
of an
outbreak
of a communicable disease, and a challenge of prediction or anticipation
of what disease outbreak (both communicable and non-communicable)
could come next (or is currently occurring but unseen). These three
challenges reveal the urgent need of a public health workforce
that is adequately trained
and supported to operate multi-disease public health surveillance
and response systems. Guinea, Sierra Leone, and Liberia do not
yet have
specific programs
to develop this workforce and the system to support them while
Nigeria does (and several other countries do) [6-8],and
this difference is critical in addressing the major public heath
challenge posed by the
current Ebola outbreak as well as a myriad of communicable and
non-communicable diseases. We will take a look at each of the three
challenges in turn.

The challenge of detecting and responding to the initial cluster of cases of an outbreak

Before a zoonotic disease outbreak occurs, there is often an outbreak in animals,
whichserve as a reservoir for the disease, and some of these disease are endemic
in the animals. Forsome species of the Ebola and Marburg filoviruses, researchers
have found antibodies in several bat species [9]. Some researchers
have also found evidence of Ebola infection in apes [10].
West Africa has a history of Lassa fever, which is carried by the multimammate
ratMastomysnatalensis [11]. Staff who are adequately trained
(meaning they have undergone experiential training) in field epidemiology, and
are working in a multi-disease surveillance and response system that is supported
adequatelywill know how to use case definitions to identify suspected cases of
viral hemorrhagic fevers, and they will also know of the need to collect and
transport specimens safely to a laboratory that can make the initial diagnosis.
These staff will also know of the need and have the training to perform an outbreak
investigation to confirm or rule out an outbreak, trace contacts, and initiate
control measures to interrupt transmission of the suspected causative agent to
the public. In several countries these field epidemiology staff have different
but complimentary background training-either as medical, or veterinary, or laboratory
scientists, each of them providing critical comparative advantages as they operate
multi-disease surveillance and response systems [6].
Most countries have guidelines and documents that define what to do for public
health surveillance and response [12], but the countries
that are able to perform well are the ones that have invested (or been supported
to invest) in developing a competently trained public health workforce and developed
the systems to support them [13]. In effect, having documents
alone without competently trained public health workers to make the decisions
that will save lives is a waste.
Missing or mishandling the initial cluster of cases often leads to an unpredictable
number of cases that can quickly overwhelm a country's public health and economic
infrastructure as we are unfortunately currently witnessing. There have been
estimates of several thousands of cases that will occur before this outbreak
is controlled, and some authors have modeled varying scenarios of the Ebola reproductive
rate (R0) from previous outbreaks which are illustrative'an R0 at 2.7 (95% CI
1.9-2.8) for the 1995 DRC epidemic and at 2.7 (95% CI 2.5-4.1) for the 2000 Uganda
outbreak [14], meaning each Ebola case could lead to up
to an average of 3 secondary cases. The economic cost of a raging outbreak is
far greater than the cost to develop a competently trained public health workforce
and implement multi-disease surveillance and response systems for them to work
in.

The challenge of managing an outbreak of a communicable disease

Outbreak management adds to outbreak investigation in several important ways,
principally in whereas outbreak investigation and confirmation are primarily
carried out by staff trained in field epidemiology, outbreak management is a
multi-sectoral, multi-skill effort, which increases in complexity with larger
outbreaks but revolves around at least fivegroups of core activities. These activities
are: a) epidemiology and surveillance to characterize the outbreak, identify
and trace contacts, and determine where the outbreak is headed and how it is
transmitted, typically done by field epidemiologists; b) case management and
infection control, to humanely treat and isolate cases while performing infection
control, and safely burying any dead patients; c) laboratory activities which
include testing specimens from suspected cases, clinical tests during treatment,
biosafety, and specimen transfers for more specialized tests; d) community activities
which include health education of all susceptible groups in the general and special
population groups (which include health workers) about how to interrupt transmission
and avoid becoming cases--the community activities are critical because they
should build trust with the affected people and enable them to cooperate to identify
suspected cases humanely; and e) activities in the environment to determine where
the reservoir and vectors of the disease are and how to address them. These five
activities are interconnected by a coordination function, which leads to decisions
on logistical needs, regulations to enforce, and vaccinations and chemoprophylaxis
if necessary. The coordination function also includes frequent, clear and transparentcommunication
with the public, the media, and authorities to build a sense of trust, effectively
a "we are in it together" common purpose to confront and end the outbreak [15].
Whereas the workforce that is needed in outbreak management is multi-sectoral,
ultimately the best decisions are guided by the data that come from competently
trained field epidemiologists who have differing background training. Several
countries coordinate large outbreaks in an emergency operations center, which
allows for a focused effort away from the usual ministry of health work [16].

The challenge of predicting the next outbreak in a country

The current Ebola outbreak suggests a challenge with predicting the occurrence
of zoonotic disease outbreaks that can be mitigated with collaboration between
the veterinary and public health sectors on zoonoses. Zoonotic disease outbreaks
will continue to occur; current data indicate that >60% of emerging or re-emerging
diseases are zoonotic, affecting people who have no immunity to these diseases
[4 ,5].
Along with zoonoses there are several disease outbreaks that have spread with
in and beyond country borders, for example West and Central Africa had a major
cholera epidemic recently [17,18].
Additionally non-communicable diseases are at epidemic levels even if they do
not provide the same level of alarm. A look at the level of hemorrhagic strokes
caused by untreated hypertension [19] or the rising levels
of obesity [20], or the unattended epidemic of mental illness
makes that point [21]. However in the case of communicable
diseases particularly zoonoses, there is an opportunity to combine veterinary
surveillance with public health surveillance to identify diseases before they
cross the "border" from animals to humans. Joint training of veterinarians and
health workers (physicians, nurses, and laboratory scientists) in field epidemiology
and laboratory training programs achieves the workforce that is needed to implement
prediction-based surveillance and response systems for zoonotic diseases [8].
New initiatives that allow the public health and veterinary sectors to combine
surveillance data using electronic methods (e.g., One Health Surveillance Initiative)
will likely facilitate prediction-based surveillance [22].
In summary the current Ebola outbreak in West Africa reveals three related public
health systems and workforce challenges that need to be addressed in order for
Africa to be able to address communicable and non-communicable disease threats.
A locally developed public health workforce that comprises medical and non-medical
personnel who are competently trained in field epidemiology and is supported
in multi-disease surveillance and response systems best addresses these challenges.
Acting now in each country large or small to implement or continue to support
these staff and systems will be cheaper than acting later, as surely these staff
and systems will be needed at some point in each country.

Competing interests

The author declares no competing interests.

Author contribution

The author has read and agreed to the final version of this manuscript and has equally contributed to its content and to the management of the case.